Timeline of key events in the scandal surrounding David Petraeus

General David Petraeus resigned as CIA director after admitting to the affair. Picture: AP /J. Scott Applewhite Source: AP

US lawmakers are demanding to know who knew what when about the investigation that led to the resignation of CIA director David Petraeus after his affair with biographer Paula Broadwell.

Here is a timeline of the key events as reported at this point:

2006: Counter-terrorism expert Paula Broadwell, a former army major, first meets Petraeus when he speaks at Harvard University. He hands her his card and offers his help when she tells him about her research interests.

2008: Mrs Broadwell, who has made her dissertation topic a case study on Petraeus's leadership, is invited to join the general for a run along the Potomac River in Washington. The keen triathlon runner later said this is when she "sealed the deal'' with the general, a renowned fitness freak, sprinting past him to the finish.

David Petraeus and Paula Broadwell pictured together.Source: Supplied

June 2010: Congress confirms Petraeus, already credited with turning around the war in Iraq, as the new commander of US forces in Afghanistan. Mrs Broadwell decides to turn her dissertation into a full-on biography.

A June 23, 2011 photo shows Paula Broadwell watching as General David Petraeus and his wife Holly Petraeus arrive for a Senate Select Intelligence Committee hearing on Petraeus' nomination to be director of the Central Intelligence Agency in the Hart Senate Office Building on Capitol Hill in Washington. Picture: Mandel Ngan/AFPSource: AFP

January 24, 2012: Release of Mrs Broadwell's book, All In: The Education of General David Petraeus.

David Petraeus has resigned after admitting to an affair with Paula Broadwell, author of the CIA chief's biography All In. Picture: APSource: AP

Jill Kelley leaves her home Monday, Nov. 12, 2012 in Tampa, Fla. Kelley is identified as the woman who allegedly received harassing emails from Gen. David Petraeus' paramour, Paula Broadwell. She serves as an unpaid social liaison to MacDill Air Force Base in Tampa, where the military's Central Command and Special Operations Command are located. AP Photo/Chris O'MearaSource: AP

Early July: Petraeus recently told friends that he ended the affair "about four months ago,'' which would mean they split up in early July.

Over the summer: Ms Kelley informs Petraeus about the threatening emails and the general in turn sends emails to Mrs Broadwell asking her to stop the harassment. It is not clear if this was before or after he ended the affair.

Late summer: High-level officials at the FBI and the Justice Department, which could include FBI chief Robert Mueller and Attorney General Eric Holder, are notified that investigators have uncovered what appears to be an extramarital affair between Petraeus and Mrs Broadwell.

October 21-27: FBI agents interview Mrs Broadwell and she acknowledges the affair and gives up her computer.

Facebook photo of Paula Broadwell with her husband Scott.Source: Supplied

Investigators find classified documents on her hard drive, raising the additional question of whether Petraeus gave them to her. She tells them he did not.

October 27: The FBI agent and friend of Ms Kelley who helped get the preliminary investigation started becomes frustrated and alerts the office of Eric Cantor, the House majority leader.

October 28-November 3: Petraeus is interviewed and says he did not give Mrs Broadwell the classified documents.

October 31: Cantor, a leading Republican opponent of President Barack Obama, passes on the concerns to FBI chief Mueller.

November 2: Mrs Broadwell is interviewed again by the FBI, according to the New York Times. Investigators have concluded that there is no national security breach and rule out filing criminal charges against anyone.

Tuesday, November 6 (ELECTION DAY): James Clapper, Obama's Director of National Intelligence, is informed of the investigation at 5:00 pm. He calls Petraeus that night and advises him to resign.

This Thursday (15 Nov) : Petraeus had been due to testify in Congress in hearings examining the September 11 attack on the US consulate in Libya that killed the ambassador and three other Americans. Acting CIA director Michael Morell will testify in his place although Petraeus may be called at a later date.

(The information comes from Paula Broadwell's biography and from anonymous law enforcement officials cited by The New York Times and The Washington Post)

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